There are numerous ways to secure to existing preformed ground surfaces objects, fixtures, structures, plates, panels, beams and other items using many different types of fastening systems and/or fasteners. The existing preformed ground surfaces could be made out of concrete, asphalt, brick, tile or many other types of materials. Most ground surface fastening systems and/or fasteners used for these types of existing preformed ground surfaces, secure the objects and/or fixtures to the ground surface semi-permanently or permanently. The objects and/or fixtures that these types of ground surface fastening systems/fasteners secure are not made to be removed frequently.
There is a marketplace need to have a fastening system or fastener which secures objects to the existing preformed ground surface, as well as, allows the object and/or fixture to be efficiently and frequently removed without having to replace the entire fastening system or fastener(s). An example of this type of application is a tactile warning surface mount plate and/or panel (TWSP). In the United States TWSP products for the visually impaired are called tactile warnings, tactile warning panels, detectable warnings, detectable warning panels or truncated domes. Tactile warnings were required in 1991 by the Americans with Disabilities Act (ADA). The ADA mandated that municipalities, governmental bodies, commercial/public buildings, shopping centers, transit platforms, loading docks, etc. utilize tactile warning panels.
A tactile warning panel is a distinctive surface pattern of domes (three-dimensional) detectable by cane or underfoot and are used to alert people with visual impairments of their approach to hazardous vehicular situations and hazardous drop-offs. The visually impaired rely on a combination of visual cues (color contrast), tactile cues (sweeping cane, sole of shoes, wheelchairs and walker wheels) and audio cues (sound) in order to identify these hazardous areas. Tactile warning panels are secured by different means to ground surfaces such as concrete pavement, asphalt pavement, sidewalks, pedestrian walkways and transit platforms. Currently, the majority of tactile warning panels (both attention and guiding patterns) are installed in fresh and/or wet set concrete or asphalt (at the time the concrete is poured or the asphalt is laid). These tactile warning panels most prevalently have a frame or fastening system on the underside of the tactile surface that gets permanently embedded into the moldable fresh and/or wet concrete or asphalt.
Tactile warning panel products having a replaceable top feature still have a bottom frame section or attached anchors that are embedded into moldable fresh and/or wet concrete or asphalt and are therefore permanent installations. U.S. Pat. Nos. 8,261,497 and 8,528,278 disclose an embedment tile with a replaceable top plate. These two patents disclose a lower portion that is permanently secured into the moldable fresh and/or wet concrete or asphalt. In addition, these patents disclose an upper panel with a downwardly extending flange around at least a portion of the perimeter of the upper panel and the flange extending downwardly to an elevation below the surface of the associated lower portion. U.S. Pat. Nos. 7,779,581 and 8,028,491 disclose a replaceable wet-set tactile warning surface unit and method of installation and replacement. These two patents require the tactile warning surface to be installed in moldable fresh and/or wet concrete. The present invention eliminates the requirement that the tactile warning panel has a frame or attached fastening system that is permanently embedded into moldable fresh and/or wet set concrete or asphalt. In addition, current surface mount style tactile warning panels not only require a mechanical anchoring system of some type but also require the use of glue and/or other adhesives to reinforce securement of the panel to the existing ground surface. These methods prevent the efficient and frequent removal and replacement of the tactile warning panel. Tactile warning panels can be damaged by vehicles, chemical corrosion, ultra violet radiation, snowplows, foot traffic, as well as, general wear and tear from the harsh outdoor environment, thus requiring regular replacement. Depending on conditions of use, a standard one-color tactile warning panel may require replacement every 2-10 years. The tactile warning panel design/decoration and proposed usage as taught in co-pending Patent Application US 2013/0212046 A1 creates an incentive to replace panels more frequently. This Patent Application relates to tactile warning panels that display text and/or other graphic information such as commercial messages, trademarks, logos, directions, slogans, pictures, names, product illustrations, emblems, promotional information related to a product or service, Quick Response Codes and other optical machine-readable labels and combinations thereof. Thus, as the messaging changes there is a need to remove and replace panels unrelated to repair or exigency. Such replacements may be desired at short intervals.